The main romances in my game aren’t bi. But the sex they’re attracted to is set when the reader picks his/her sex.
If writing characters like that is disturbing to you, then do go ahead and offer a variety of romance options, as others have suggested.
If I play a monkey in a game, it doesn’t mean I like peanuts. (But it’s possible that I first realize I like peanuts when playing a monkey.) Still, the answer to your question as written is no.